The band are called 'Godspeed You Black Emporer' the album is titled "F# A# Oo."
The track is called East Hastings.
It appears in the film 28 Days Later. But, not on the soundtrack to the film.
Nope, it's definately John Murphy's "In the House - In a Heartbeat". I'm listening to that very track now, it's definately this track, beyond shadow of a doubt.